Microphotoluminescence studies of polycrystals were performed. At room temperature, two photoluminescence (PL) bands were detected at 1.39 and 1.53 eV and attributed to band-to-tail (BT) and band-to-band (BB) recombination, respectively. At lower temperatures, band-to-impurity recombination always dominates. The results show that the model of heavily doped semiconductors applies to and that, in contrast to the ternary chalcopyrites, the BT recombination in has very low intensity. The laser power dependency of the PL intensity shows that the recombination mechanism of BT and BB bands exhibits an exciton-like behavior.